Radioreceiver and resistance cord



Oct. 23, 1934. g T MASON ET AL 1,978,053

RADIOREGEIVER AND RESISTANCE CORD Filad Feb. 13, 1935 2 Sheets-Sheet 1 LI Q 9 CarL mada Oct. 23, 1934-. c MASQN r AL 1,978,053

RAISIORECEIVER AND RESISTANCE CORD Filed Feb. '15, 1955 2 Sheets-Sheet 2Jiadw Becewer m0 Baal/6r desirable,

Patented Oct. 23, 1934 1,91s,c5s nsnroascarvaa AND RESISTANCE'CO Carl T.Mason and Byron B. Minnium, Chicago, IlL, assignors to Stewart-WarnerCorporation, Chicago, 111., a corporation of Virginia ApplicationFebruary 13, 1933, Serial No. 356,438 2. Claims. (Cl. 250-27) Thisinvention relates toa new and improved electrical conductor .cord or thelike, and more particularly to a multiple conductor including both highand low resistance units.

5 With various types of devices to be Operated from regular commercialelectric current lines,

it is desirable or necessary to reduce the voltage between the line andthe device being operated. Examples of such devices are radio sets andmotion picture projectors. With many such devices it is customary tolocate the resistance within the set or under or .upon the mounting ofthe projector. The usual types of resistances are bulky and must beprovided with ventilation to dissipate 5 the heat generated during theuse of the resistance. Both of these difficulties are particularlyobjectionable in connection with certain types of small radio sets whichhave been developed for use upon commercial current .lines whether digorect or alternating current.

We tion in relation to such a radio set but it is to be understood thatit is adapted for a wide variety of other uses where a resistance isnecessary or such as in connection with motion picture projectors, smallmotors, therapeutic lamps or other devices. a

It is an object of the present invention to proyide a new and improvedelectrical conductor 39 cord or the like including a high resistanceelement.

It is also an object to provide a multiple con-' ductor including bothlow and high resistance conducting elements.

'It is an additional object to provide a multiple conductor includinglow and high resistance units connected in parallel.

It is a further object to provide a miultiple'conductor of the-typedescribed in which the high and low resistance elements are insulatedfrom each other both electrically and thermally.

' It is also an object to provide a multiple conductor adapted for usewith difierent voltages of supply current and adapted for adjustment inaccordance with such voltage.

Other and further objects description proceeds.

We have shown in the accompanying drawings certain preferred embodimentsoi. our invention. Figure 1 is a diagrammatic showing oi a radio circuitwith our improved conductor in association therewith;'

Figures 2, 3, 4 and 5 are \views similar to Figure 1, with the radioreceiver merely indicated in the will appear as the have illustrated anddescribed our invenfigures and with modified forms of conductor showndiagramatically; j

Figure-6 is a section on an enlarged scale taken on line 66 of Figure 2;

Figure '7 is an enlarged section 7-7 of Figure 3;

Figure 8 is a view similar to Figure 2, but showing a modified form ofconductor;

Figure 9 is a section on line 9-9 01 Figure 8; and i I i r 5 Figure 10is a view similar to Figure 8 but showing a further modification;

Referring first to Figure l, the radio circuit is shown in schematicform including the radio frequency amplifying tube 11, the detector tube12 and audio amplifying tube 13. The rectifier tube is shown at 14.Themultiple conductor 15 is shownfas provided with a usual type of,twoprong plug 16 having. rongs 17 and 18 adapted for insertion in anyusual type of receptacle. The prong 17 is connected to the lowresistance conductor 19, which conductor is connected to the electrode20 in the rectifier tube 14.

The low resistance conductor 21 is connected to prong 18 and in the setis connected through line 22 to line 23 which, through line 24, isconnected to the filament or heater element 25 in the detector tube 12..This element 25 in tube. 12 is connected by wire 26 to the similarelement 2'? in tube 11. Element 27 is connected by the wire 28 to thesimilar element 29 in tube 13 The other side of the element 29 isconnected through wire 30 to the element 31 in the rectifier tube 14.

taken on line 60 The other side of element 31 is connected by wire 32 tothe high resistance conductor 33 in the multiple conductor 15. This highresistance conductor 33 is connected in; parallel in the conductor 15 tothe low resistance conductor 19 a at a point adjacent the plug 16.

It will be understood that the'hig-h resistance conductor 33 may be ofany desired length and extend through any part of the multiple conductor15, depending upon the resistance of the wire use in conductor. 33, thelength of the multiple conductor, and the amount of resistance it isdesired to insert in the line.

With four tubes of the type shown in use in radio sets at theprese'nttime, and with the filaments connected in series, the resistancein the conductor 33 should be approximately 280 ohms, with a volt sourceof current. It will'be understood that the showing of Figure ,1 isschemat-. lo and that the invention is adapted for use with other typesof radio circuits in which tubesmay be connected in series or inparallel as desired, deno pending upon the tube characteristics and thevoltage of the line. It will also be understood two low resistanceconductors, the proper voltage drop may be provided between theelectrodes in the rectifier tube as well assupplying the filamentcurrent for all of the tubes, which latter our- 7 rent is passed inseries through the high resistance conductor. In Figure 1 the threeconductor elements have been shown schematically as carried in parallelthrough the multiple conducton. This form of construction may be used orthe forms of construction shown in Figures 2 and 3,

which merely differ as to the relation to the three conducting elements.

- eludes-the low resistance conductors 51 and 52 provided with theinsulating sheaths 53 and 54.

. In'Figure 2 the low resistance conductors 40 and 41 are shown twistedwith thehigh resistance conductor 42. This multiple conductor is shownin section on an enlarged scale in Figure 6. The low resistanceconductors 40 and 41 are shown as provided with insulating casings orsheaths 43 and 44. These casings or sheaths may be formed of, fabric andrubber, or any other usual insulating material. The high resistanceconductor 42 is shown as consisting of a spiral coil which is wrappedspirally around a core 45- and is enclosed in a sheath 46'. This-sheath46 in addition to beingan electrical insulator is also preferablyprovided with one or more layers of asbestos or other The threeconductors The form of construction shown in Figure 3 in Theseconductors 51 and 52 are carried parallel and spirally wrapped aroundthem is a high resistance conductor 55; The conductor 55 is in turnenclosed in an asbestos sheath '56 with an outer fabric covering 57.

The forms of construction shown in Figures 4 and 5 diiier from thosepreviously described in that the high resistance conductonextends onlypart way through the'length of themultiple conductor. In the tube shownin Figure 4, the insulating housing 61 encloses the lowresistanceconductors 62 and 63 and the high resistance conductor 64.These conductors are. connected to usual types of wires or otherflexible low resistance conductors 65, 66 and 67 respectively, thesewires leadingito the radio receiver. The sheath 61 may be of greater orless longitudinal extent and may be directly incorporated in a plugstructurehaving the prongs 68 and 69 for the usual type of connector.The housing 61 may be'both thermally and electrically insulated and ifdesired my be flexible in character. I s In the form of constructionshown in Figure 5,

the plug 71- is provided with prongs '12 and 73- which connect to wires74 and 75. The wire- 75 connects in the sheath or housing 76 to the highresistance conductor 77 and the low resistance conductor 78. The wire 74connects in the hou's ing 76 to the low resistance conductor 79. In thiscase the housing or sheath is located immediate- Lv adjacent the radioreceiver rather than adjacent the plug. Where the extension of such ahousing adjacent the receiver is not objection able, thisconstruction-has the advantage over that in Figure 4 in that onlytwoconductor wires are necessary between the housing and the plug. Inthe form of constructionshown in Figure 8,-

the proper voltage to the receiver.

there is provided an adjustably connected plug '81 which includes thesection 82 provided with nected to prong 83 in all of the three adjustedpositions of the plug.

With the parts in the intermediate position. shown in Figure 8, thecontact connected to the wire 87 is aligned and in contact with thecontact connected to prong 84. The contact 91 would be permanentlyconnected to the low resistance wire 86, and contact 92 connected to thehigher resistance wire 88. The multiple conductor has been shownconnected to a radio receiver 93. Whilean adjustable multiple conductorof this character is adapted for use with a variety of current-usingdevices, it has been shown in connection with the radio receiver andvoltages V 1 of 6, 32 and 110 have been indicated on the plug section81-. For example, where the source of voltage connected through prongs83 and 84 is a storage battery or other device delivering six, volts,the two low resistance conductors 85 and 86 may be connected. Ifthevoltage delivered is 32 volts, as for example from what are commonlycalled farm lighting systems, the resistance of the line 87 may beadequate taken in connection with the low resistance conductor 85 todeliver For use with a 110 volt source of current the high resistance 88may be connected in association with the low resistance conductor 85.

The form of construction shown in Figure 10 offers a possibility ofdelivering a multiplicity of I voltages to a radio receiver or any otherdevice from a source 01 current having asingle voltage. The plug 101 isshown as having the prong 102 which is connected to a low resistancewire 103 and a high resistance wire 104. The prong ,105 is shownconnected to a low resistance wire 106,- a high resistance wire 107, anda higher resistance wire 108. All wires lead to the radio receiver 109;It will be apparent that cross connections may be made in thereceiver ina variety oil-ways between the several conductors which vary inresistance. For example, a cross connection be-v tween conductor 104 andconductor 108 would give a low voltage. A connection between conductor104 and conductor 107 would g'ive'a higher voltage. A connection betweenconductor 104 a connection between conductors 103 and'106' would deliverto the receiver or other device, substantially the full voltage of thepower line. It -will be apparent, therefore, that a multiple conductorof this character is adapted to deliver a multiplicity of voltages andthus eliminate the necessity for numerous resistors which are com-Xmonly used in radio receivers.

While the drawings have shown several types of construction it will beunderstod that our invention is capable of either change or modificationto meet varying conditions and requirements. Also, as has beenpreviously stated, it

a radio receiver.

ducting elements being connected in series with said vacuum tube, thehigh resistance element to the filament of said tube and the lowresistance element to another electrode in said tube.

-2. In combination with a radio receiving set having a receiving vacuumtube and a rectifying vacuum tube as parts thereof, a multipleelectrical conductor external to trically connected between said set anda high potential source of current,'a pair of low resistance conductingelements and a. high resistance conducting element in said conductor,the high resistance element and one low resistance element beingconnected in series with the filaments oi the receiving and rectifyingtubes, and the other low resistance element being connected in parallelwith the high resistance element and to an electrode in the rectiiyingtube. 1

- CARL T. MASON.

BYRON B.-

said radio setand elec-'

